Deformable energy storage devices are emerging as indispensable components for unconventional electronics devices that are able to survive significant degrees of deformation, mainly bending and stretching, with strain levels much greater than 1%. Examples include flexible displays, stretchable circuits, hemispherical electronic eyes, and epidermal electronics. The energy storage devices present a significant challenge for developing a robust deferrable system, since they must be seamlessly integrated with deformable functional devices and energy supplies with similar mechanical characteristics, including linear deform ability (i.e., stretchability and compressibility), bendability, and twistability. For bending deformation, thin film based energy solutions such as supercapacitors and batteries have been developed that take advantage of the inherently small strains (usually less than 1%) near the mechanical neutral planes.
Recently, progress has been made in the development of stretchable energy sources. Stretchable supercapacitors using buckled carbon nanotube (CNT) macrofilms as electrodes and CNT-coated porous conductive textiles have been developed, as well as stretchable lithium-ion batteries (LIBs). However, approaches that simultaneously achieve a high level of deformability (including linear stretching and compression, bending, twisting and combinations thereof) with large areal coverage that are compatible with commercially available manufacturing technologies are lacking.
Therefore, there remains a need for flexible and stretchable batteries that remains functional, and can be integrated with electronic devices.